On May 3, 1917, French troops in some of the regiments that had suffered the greatest casualties in Commander in Chief Robert Nivelle's Chemin des Dames Offensive mutinied, with actions that spread to 16 army corps in four armies, and led to civilian sympathy strikes. On May 15, War Minister Paul Painlevé replaced Nivelle with Henri Pétain, who had commanded the defense of Verdun. By that time, the Fourth, Fifth, Sixth, Tenth Armies had seen soldiers refuse to attack or to move to the front, violence in railway stations, and threats to march on Paris.

On May 19, Pétain issued his Directive #1 to end the mutinies. Pétain's carrots were assurances to soldiers that he would not squander their lives, and that France would build the weapons of war—tanks, heavy artillery, aircraft—that would bring victory. His stick was the suppression of the mutinies by force, with trials, imprisonment, and executions. Earlier in the war, French commanders had abused cours martiales, in which soldiers had no appeal beyond the army itself. These were replaced by conseils de guerre, in which the convicted retained a right of appeal to a higher court, and death sentences had to be approved by the President. Pétain insisted on retaining courts martial, with his own approval being required and final, until the mutinies were controlled. Prime Minister Paul Painlevé reasserted his authority on July 14, when the mutinies were clearly drawing to a close.

Pétain court-martialed over 100,000 soldiers, of whom 22,000 were found guilty, 432 sentenced to death, and 55 officially shot, although more may have been shot without sentence. Pétain also sought to addressed many of the soldier’s grievances. He improved conditions for the soldiers, ensuring they received leave, visiting the front, and insisting officers attend to their men.